Polyethylene glycol as a robust, biocompatible encapsulant for two-stage treatment of food and beverage wastewater
Polyethylene glycol beads encapsulating anaerobic microbes developed for on-site food and beverage wastewater treatment.
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Polyethylene glycol beads encapsulating anaerobic microbes developed for on-site food and beverage wastewater treatment.
Abstract Through advances in molecular design, understanding of processing parameters, and development of non‐traditional device fabrication techniques, the field of wearable and implantable skin‐inspired devices is rapidly growing interest in the consumer market. Like previous technological advances, economic growth and efficiency is anticipated, as these devices will enable an augmented level of interaction between humans and the environment. However, the parallel growing electronic waste that is yet to be addressed has already left an adverse impact on the environment and human health. Looking forward, it is imperative to develop both human‐ and environmentally‐friendly electronics, which are contingent on emerging recyclable, biodegradable, and biocompatible polymer technologies. This review provides definitions for recyclable, biodegradable, and biocompatible polymers based on reported literature, an overview of the analytical techniques used to characterize mechanical and chemical property changes, and standard policies for real‐life applications. Then, various strategies in designing the next‐generation of polymers to be recyclable, biodegradable, or biocompatible with enhanced functionalities relative to traditional or commercial polymers are discussed. Finally, electronics that exhibit an element of recyclability, biodegradability, or biocompatibility with new molecular design are highlighted with the anticipation of integrating emerging polymer chemistries into future electronic devices.
Creating biobased polymer blends with outstanding properties, nanoscale morphology, shape-memory capability, and biocompatibility is very crucial and requires a fundamental understanding of the phase behavior, macromolecular structure, and biological compatibility of the polymer blends with living cells. It is very critical to understand the complex relationships among the polymer structure, morphology, and performance of multifunctional smart materials under conditions that they are likely to encounter during use, particularly in biomedical applications. Biobased semi-interpenetrating polymer networks of poly(ε-caprolactone) and epoxidized soybean oil with nanoscale morphology have been successfully synthesized via in situ cationic polymerization and compatibilization in a homogeneous solution. Varies analytical and characterization techniques, such as Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical analysis, transmission electron microscopy, X-ray scattering, cell toxicity, and shape-memory effects (SMEs), have been employed to understand the structure–properties relationship of these smart, biobased nanostructured polymer blends. The synthesized nano blends were nontoxic or biocompatible and supported attachment of human vein endothelial cells, showing their potential use in biomedical applications. The current versatile, low-cost strategy for synthesizing the nanoscale morphology of semi-interpenetrating polymer networks with SMEs and biocompatibility should be widely applicable for polymer systems. This study is also considered as a continuation to our efforts in the area of biobased polymers to develop innovative technologies to transform natural resources into smart multifunctional materials for a wide range of applications, including coatings, adhesives, and medical devices.
Biomass deconstruction is a crucial step in the production of lignocellulosic biofuels and bioproducts. However, identifying and selecting an optimal pretreatment solvent that enhances enzymatic saccharification while being cost-efficient and ensuring sustainability remains a challenge. In this study, we compare the effectiveness of the biocompatible ionic liquid cholinium lysinate ([Ch][Lys]) against the distillable solvent ethanolamine, when used for the pretreatment of mixed bioenergy feedstocks, including poplar, switchgrass, and sorghum. [Ch][Lys] was used at a concentration of 10 % wt. in a one-pot configuration without biomass washing and ethanolamine was used in a concentrated form and removed with a vacuum oven, before performing enzymatic hydrolysis and microbial conversion. Our results show that ethanolamine pretreatment consistently enhances the glucose yield across various biomass types compared to [Ch][Lys], with improvements ranging from 22.0 % to 52.7 %. The highest combined sugar release was observed when the three feedstocks were combined in equal amounts and pretreated with ethanolamine, achieving a glucose yield of 84.6 % and a xylose yield of 76.6 %. Additionally, ethanolamine exhibited exceptional solvent recovery efficiency, with removal efficiencies exceeding 99.8 % at 120 °C across all feedstocks, highlighting its advantage over non-distillable solvents. While both solvents produced biocompatible hydrolysates, the hydrolysates prepared using ethanolamine resulted in higher bioproduct formation. These findings highlight the industrial relevance of selecting recyclable and biocompatible solvents for scalable, sustainable, and cost-effective bioenergy production. This study contributes to the development of economically viable and scalable pretreatment technologies for bioenergy applications using different feedstocks and process configurations.
Abstract Background Agriculture faces significant global challenges including climate change and an increasing food demand due to a growing population. Addressing these challenges will require the adoption of transformative innovations into biotechnology practice, such as nanotechnology. Recently, nanomaterials have emerged as unmatched tools for their use as biosensors, or as biomolecule delivery vehicles. Despite their increasingly prolific use, plant-nanomaterial interactions remain poorly characterized, drawing into question the breadth of their utility and their broader environmental compatibility. Results Herein, we characterize the response of Arabidopsis thaliana to single walled carbon nanotube (SWNT) exposure with two different surface chemistries commonly used for biosensing and nucleic acid delivery: oligonucleotide adsorbed-pristine SWNTs, and polyethyleneimine-SWNTs loaded with plasmid DNA (PEI-SWNTs), both introduced by leaf infiltration. We observed that pristine SWNTs elicit a mild stress response almost undistinguishable from the infiltration process, indicating that these nanomaterials are well-tolerated by the plant. However, PEI-SWNTs induce a much larger transcriptional reprogramming that involves stress, immunity, and senescence responses. PEI-SWNT-induced transcriptional profile is very similar to that of mutant plants displaying a constitutive immune response or treated with stress-priming agrochemicals. We selected molecular markers from our transcriptomic analysis and identified PEI as the main cause of this adverse reaction. We show that PEI-SWNT response is concentration-dependent and, when persistent over time, leads to cell death. We probed a panel of PEI variant-functionalized SWNTs across two plant species and identified biocompatible SWNT surface functionalizations. Conclusions While SWNTs themselves are well tolerated by plants, SWNTs surface-functionalized with positively charged polymers become toxic and produce cell death. We use molecular markers to identify more biocompatible SWNT formulations. Our results highlight the importance of nanoparticle surface chemistry on their biocompatibility and will facilitate the use of functionalized nanomaterials for agricultural improvement. Graphical Abstract
An anti-viral coating for the nose & throat is needed to quickly address the spread of COVID-19 infections and to aid future pandemics. Current nasal delivery systems are typically a 1-spray homogenous solution, which is convenient but may not be as efficient or durable as a multi-spray solution that contains a binding layer to anchor the anti-viral components. Many of the current nasal solutions being investigated to aid in pandemic response have solution-based mechanisms of action and are quickly cleared from the nose/mouth limiting their efficacy lifetime. A multi-spray approach utilizing strong intermolecular forces between polymeric materials and anti-viral agents to provide a robust biocompatible coating is expected to have increased physical and chemical properties to combat viral infection. This work evaluated which tailored biocompatible materials are needed to generate a layered system to combat viral infection. This layered system takes advantage of electrostatic interactions to bind anti-viral components, shown in Figure 1. Proof of concept success was demonstrated through cell toxicity studies and anti-viral assays on both the individual layer components and the complete layered system. Project work began with chemical modifications of Xantham Gum to hydrolyzing xanthan gum to give a negatively charged polymer with varying degrees of ionic character and investigate bonding efficiencies. However, this was abandoned in favor of comparing COTS available materials listed in Table 1 (Results section). Concentration and adhesion studies were performed on layers created using the listed polymeric materials and anti-viral agents. Finally, biocompatibility of materials, layers, and coating system were confirmed through cytotoxicity studies and the efficacy of the anti-viral properties tested with phi6 bacteriophage as a SARS-CoV2 surrogate.
Agave bagasse (AG) is a potential bioenergy feedstock due to its high biomass productivity, even in semiarid lands. In particular, ionic liquid (IL) pretreatment using aprotic ILs (AILs) has greatly reduced AG recalcitrance towards downstream processing by lowering lignin content and achieving high sugar yields. However, AIL's low biocompatibility towards enzymes and bacteria combined with the high initial cost has limited further development of this technology. In a wash-free one-pot (OP) ethanol conversion process, the evaluation of AG pretreatment with a biocompatible low-cost protic IL (PIL), 2-hydroxyethylammonium acetate ([2-HEA][OAc]) was achieved, where PIL pretreatment was followed by enzymatic saccharification, then ethanol fermentation in a single vessel. The pretreatment conditions were optimized using a central composite design to enable high sugar conversion at low PIL content. Under optimized pretreatment conditions (160 °C, 60% IL loading and 1.5 h), a yield of 132 kg of ethanol per Ton of untreated biomass was estimated using high solids loading (30% solids loading) under a PIL-OP scheme. High lignin removal (>50%), a decreased cellulose crystallinity, and high glucan conversion (>85%) were achieved with PIL-pretreated AG comparable to yields obtained in an AIL-AG pretreated sample using 1-ethyl-3-methyl-imidazolium acetate ([C 2 C 1 Im][OAc]). Here, these results using [2-HEA][OAc] demonstrate the potential of AG in an OP scheme with improved total ethanol yields paving the way towards a more feasible IL-based biorefinery.
Research on polymer materials for additive manufacturing technology in biomedical applications is as promising as it is numerous, but biocompatibility of printable materials still remains a big challenge. Changes occurring during the 3D-printing processes itself may have adverse effects on the compatibility of the completed print. Furthermore, this prospective will put emphasis on the different additives and processes that can have a direct impact on biocompatibility during and after 3D printing of polymer materials.
Method of selecting biocompatible materials for surgical implants uses fracture mechanic relationships and surface energies of candidate materials in presence of blood plasma. Technique has been used to characterize 190 materials by parameters that reflect their biocompatibility.
The European Modular Cultivation System (EMCS) is an European Space Agency-developed facility designed to support plant research in microgravity on the IS NASA is responsible for providing US specific hardware to use within the EMCS. In preparation for flight, research will be developed and tested at Ames Research Center in the EMCS ground test hardware, the Experiment Reference Module (ERM) In order to determine the acceptability of the ERM for such purposes, biocompatibility tests will be performed to determine that the hardware functions as intended and successfully supports the' growth of plants. In this report, we describe the development of procedures and the collection of baseline data against which to compare ERM function, e.g. biocompatibility testing. A simple and robust system was developed to grow whole Arabidopsis thaliana plants within the confined volumes characteristic of spaceflight hardware. Our system for growing plants eliminated the necessity of a water/nutrient delivery system and allowed for quantifiable assessment of individual plants, as well as entire population dynamics. To insure uniform germination, seeds were started in small straw segments and transplanted into modified scintillation vials. Seedlings were selected prior to transplantation to decrease genetic variability. Plants were grown for a total of 24 days in standard laboratory plant growth chambers under controlled conditions. Sequential digital still images were taken on a daily basis. Analysis of these images allowed for the quantification of even minute environmental effect, on growth dynamics whole plants. The data collected provide reliable growth curves against which to compare plants grown in the ERM.
Epoxy has been used successfully to affix NASA foodbars to the inner walls of the Animal Enclosure Module for past space flight experiments utilizing rodents. The epoxy used on past missions was discontinued, making it necessary to identify a new epoxy for use on the STS-108 and STS-107 missions. This experiment was designed to test the basic biocompatibility of epoxy EP21LV with male rats (Sprague Dawley) and mice (Swiss Webster) when applied to NASA foodbars. For each species, the test was conducted with a control group fed untreated foodbars and an experimental group fed foodbars applied with EP21LV. For each species, there were no group differences in animal health and no statistical differences (P<0.05) in body weights throughout the study. In mice, there was a 16% increase in heart weight in the epoxy group; this result was not found in rats. For both species, there were no statistical differences found in other organ weights measured. In rats, blood glucose levels were 15% higher and both total protein and globulin were 10% lower in the epoxy group. Statistical differences in these parameters were not found in mice. For both species, no statistical differences were found in other blood parameters tested. Food consumption was not different in rats but water consumption was significantly decreased 10 to 15% in the epoxy group. The difference in water consumption is likely due to an increased water content of the epoxy-treated foodbars. Finally, both species avoided consumption of the epoxy material. Based on the global analysis of the results, the few parameters found to be statistically different do not appear to be a physiologically relevant effect of the epoxy material, We conclude that the EP21LV epoxy is biocompatible with rodents.
Here, we report a potential biomedical material, NbTaTiVZr, and the impact of surface roughness on the osteoblast culture and later behavior based on in vitro tests of preosteoblasts. Cell activities such as adhesion, viability, and typical protein activity on NbTaTiVZr showed comparable results with that of commercially pure Ti (CP-Ti). In addition, NbTaTiVZr with a smooth surface exhibits better cell adhesion, viability, and typical protein activity which shows that surface modification can improve the biocompatibility of NbTaTiVZr. This supports the biological evidence and shows that NbTaTiVZr can potentially be evaluated as a biomedical material for clinical use.
Metallic glasses represent a class of metallic alloys with a fully amorphous structure and attractive properties, making them promising in bioimplant applications. Here, the degradation tolerance of biocompatible cobalt–phosphorus (Co–P) metallic glasses was studied in a simulated physiological environment. The metallic glasses were synthesized in the form of coatings through a facile electrodeposition approach. This method utilizes their outstanding surface characteristics and bypasses the size limitations usually associated with their bulk counterparts. Further, the Co–P alloys showed exceptional tribological response with ~14% lower coefficient of friction and 2 orders of magnitude lesser wear rate compared to SS316 stainless steel. In addition, the Co–P alloys showed a 3 times higher hardness and 4 times higher hardness/modulus ratio compared to SS316, indicating better elastic recovery under dynamic shear stresses that are common in load-bearing bioimplants. The Co–P metallic glasses exhibited excellent hemocompatibility and cytocompatibility in terms of lower platelet adhesion, spreading, and aggregation, a hemolysis ratio lower than 1%, and enhanced surface wettability, suggesting a superlative performance in bioimplant applications.
Abstract The ability to replicate the microenvironment of biological tissues creates unique biomedical possibilities for stem cell applications. Current fabrication methods are limited by either the control on feature size and shape, or by the throughput and size of the replicas. Here, a novel platform is reported that combines thermal scanning probe lithography (tSPL) with innovative methodologies for the low‐cost and high‐throughput nanofabrication of large area quasi‐3D bone tissue replicas with high fidelity, sub‐15 nm lateral precision, and sub‐2 nm vertical resolution. This bio‐tSPL platform features a biocompatible polymer resist that withstands multiple cell culture cycles, allowing the reuse of the replicas, further decreasing costs and fabrication times. The as‐fabricated replicas support the culture and proliferation of human induced mesenchymal stem cells, which display broad therapeutic and biomedical potential. Furthermore, it is demonstrated that bio‐tSPL can be used to nanopattern the bone tissue replicas with amine groups, for subsequent tissue‐mimetic biofunctionalization. The achieved level of time and cost‐effectiveness, as well as the cell compatibility of the replicas, make bio‐tSPL a promising platform for the production of tissue‐mimetic replicas to study stem cell‐tissue microenvironment interactions, test drugs, and ultimately harness the regenerative capacity of stem cells and tissues for biomedical applications.
Advanced manufacturing has received considerable attention as a tool for the fabrication of cell scaffolds however, finding ideal biocompatible and biodegradable materials that fit the correct parameters for 3D printing and guide cells to align remain a challenge. Herein, a photocrosslinkable smectic-A (Sm-A) liquid crystal elastomer (LCE) designed for 3D printing is presented, that promotes cell proliferation but most importantly induces cell anisotropy. The LCE-based bio-ink allows the 3D duplication of a highly complex brain structure generated from an animal model. Vascular tissue models are generated from fluorescently stained mouse tissue spatially imaged using confocal microscopy and subsequently processed to create a digital 3D model suitable for printing. The 3D structure is reproduced using a Digital Light Processing (DLP) stereolithography (SLA) desktop 3D printer. Synchrotron Small-Angle X-ray Diffraction (SAXD) data reveal a strong alignment of the LCE layering within the struts of the printed 3D scaffold. The resultant anisotropy of the LCE struts is then shown to direct cell growth. This study offers a simple approach to produce model tissues built within hours that promote cellular alignment.
Simultaneous valorization of both carbohydrate and lignin fractions in lignocellulose remains a great challenge. Herein, a novel lignin-first strategy using triethylene glycol (TEG) under alkaline conditions for effective biomass fractionation producing highly digestible carbohydrates and reactive lignin was developed. Delignification was over 80% and fermentable sugar yields were close to 90% after pretreatment at 90°C. The biocompatibility of TEG allowed direct enzymatic hydrolysis of the solid residue without washing, thus minimizing wastewater generation. Furthermore, the obtained lignin (TEGL) had an uncondensed structure with well-preserved β-O-4 linkage, leading to near-equal aromatic monomer yields compared to cellulolytic enzyme lignin after catalytic-free pyrolysis, demonstrating high valorization potential. Finally, the proposed TEG solvent system is promising for a green and sustainable biorefinery process to achieve the complete utilization of lignocellulose.
CMOS-based computing systems that employ the von Neumann architecture are relatively limited when it comes to parallel data storage and processing. In contrast, the human brain is a living computational signal processing unit that operates with extreme parallelism and energy efficiency. Although numerous neuromorphic electronic devices have emerged in the last decade, most of them are rigid or contain materials that are toxic to biological systems. In this work, we report on biocompatible bilayer graphene-based artificial synaptic transistors (BLAST) capable of mimicking synaptic behavior. The BLAST devices leverage a dry ion-selective membrane, enabling long-term potentiation, with ~50 aJ/µm 2 switching energy efficiency, at least an order of magnitude lower than previous reports on two-dimensional material-based artificial synapses. The devices show unique metaplasticity, a useful feature for generalizable deep neural networks, and we demonstrate that metaplastic BLASTs outperform ideal linear synapses in classic image classification tasks. With switching energy well below the 1 fJ energy estimated per biological synapse, the proposed devices are powerful candidates for bio-interfaced online learning, bridging the gap between artificial and biological neural networks.
High-entropy alloys (HEAs) have attracted great attention due to their many unique properties and potential applications. The nature of interatomic interactions in this unique class of complex multicomponent alloys is not fully developed or understood. We report a theoretical modeling technique to enable in-depth analysis of their electronic structures and interatomic bonding, and predict HEA properties based on the use of the quantum mechanical metrics, the total bond order density (TBOD) and the partial bond order density (PBOD). Application to 13 biocompatible multicomponent HEAs yields many new and insightful results, including the inadequacy of using the valence electron count, quantification of large lattice distortion, validation of mechanical properties with experiment data, modeling porosity to reduce Young’s modulus. This work outlines a road map for the rational design of HEAs for biomedical applications.